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2020 2

2018 3

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一水硬铝石 1

氧化铝 1

氧化铝管道化溶出 1

白炭黑 1

磨损 1

粉煤灰 1

综合利用 1

节能降耗 1

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Grindability of high-temperature alloy with ceramic alumina wheels

ZHANG Hongxia, CHEN Wuyi, CHEN Zhitong

《机械工程前沿（英文）》 2008年第3卷第2期页码 139-145 doi: 10.1007/s11465-008-0040-3

摘要： The grindability of high-temperature alloy by using ceramic alumina wheels is studied on the basis of extensive analysis of the grinding force, grinding temperature, surface roughness and topography of ground surfaces, residual stress, hardness distribution of surface layer, and morphology of the surface layer from a metallographic point of view. The grinding burn mechanism of high-temperature alloy is unveiled and the feasible grinding parameters to avoid burning are analyzed. Some conclusions are obtained as follows. Increasing the grinding depth or the wheel velocity makes grinding temperature and residual tensile stress of the surface rise, which deteriorates the surface topography. Appropriate liner velocity of the wheel is 18–22 m/s and the depth of grinding should not exceed 0.02 mm in grinding GH2132 alloy with ceramic alumina wheels to assure the surface quality. When increases enough to cause grinding burn, the strengthening effect of particles ′ in base decrease and the micro-hardness of the surface is obviously lower than that of the base material, which deteriorates the mechanical properties and heat resistance of GH2132 alloy. Results provide a theoretical and experimental basis for technical optimization in the grinding of high-temperature alloy with high efficiency and high quality.

关键词： metallographic topography grinding GH2132 resistance decrease

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Room temperature oxidation of acetone by ozone over alumina-supported manganese and cobalt mixed oxides

Mehraneh Ghavami, Mostafa Aghbolaghy, Jafar Soltan, Ning Chen

《化学科学与工程前沿（英文）》 2020年第14卷第6期页码 937-947 doi: 10.1007/s11705-019-1900-6

摘要： Volatile organic compounds (VOCs) are among the major sources of air pollution. Catalytic ozonation is an efficient process for removing VOCs at lower reaction temperature compared to catalytic oxidation. In this study, a series of alumina supported single and mixed manganese and cobalt oxides catalysts were used for ozonation of acetone at room temperature. The influence of augmenting the single Mn and Co catalysts were investigated on the performance and structure of the catalyst. The manganese and cobalt single and mixed oxides catalysts of the formula Mn10%-CoX and Co10%-MnX (where X= 0, 2.5%, 5%, or 10%) were prepared. It was found that addition of Mn and Co at lower loading levels (2.5% or 5%) to single metal oxide catalysts enhanced the catalytic activity. The mixed oxides catalysts of (Mn10%-Co2.5%) and (Mn10%-Co5%) led to acetone conversion of about 84%. It is concluded that lower oxidation state of the secondary metal improves ozone decomposition and oxidation of acetone.

关键词： ozone VOC manganese oxides cobalt oxides alumina support

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Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 415-421 doi: 10.1007/s11705-013-1360-3

摘要： Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques: Brunner-Emmett-Teller-N adsorption-desorption for surface area, temperature programmed desorption of NH and -butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between -phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction parameters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关键词： alumina manganese oxide deposited on alumina quinoxaline synthesis

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Alumina modified sodium vanadate cathode for aqueous zinc-ion batteries

《能源前沿（英文）》页码 775-781 doi: 10.1007/s11708-023-0902-8

摘要： Aqueous zinc-ion batteries (ZIBs) have great prospects for widespread application in massive scale energy storage. By virtue of the multivalent state, open frame structure and high theoretical specific capacity, vanadium (V)-based compounds are a kind of the most developmental potential cathode materials for ZIBs. However, the slow kinetics caused by low conductivity and the capacity degradation caused by material dissolution still need to be addressed for large-scale applications. Therefore, sodium vanadate Na₂V₆O₁₆·3H₂O (NVO) was chosen as a model material, and was modified with alumina coating through simple mixing and stirring methods. After Al₂O₃ coating modification, the rate capability and long-cycle stability of Zn//NVO@Al₂O₃ battery have been significantly improved. The discharge specific capacity of NVO@Al₂O₃ reach up to 228 mAh/g (at 4 A/g), with a capacity reservation rate of approximately 68% after 1000 cycles, and the Coulombic efficiency (CE) is close to 100%. As a comparison, the capacity reservation rate of Zn//NVO battery is only 27.7%. Its superior electrochemical performance is mainly attributed to the Al₂O₃ coating layer, which can increase zinc-ion conductivity of the material surface, and to some extent inhibit the dissolution of NVO, making the structure stable and improving the cyclic stability of the material. This paper offers new prospects for the development of cathode coating materials for ZIBs.

关键词： cathodes aqueous zinc-ion batteries sodium vanadate alumina coating

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Effect of alumina and zirconia as binders on the activity of Fe-BEA for NH

Jin Shi, Zihao Zhang, Mingxia Chen, Zhixiang Zhang, Wenfeng Shangguan, Shunchao Gu, Hirano Shin-ichi

《环境科学与工程前沿（英文）》 2018年第12卷第1期 doi: 10.1007/s11783-018-1012-4

摘要： Fe-BEA catalysts are active for the NH -SCR of NO. For industrial application, a binder should be added to the Fe-BEA catalysts to make them tightly adhere to the monoliths. The addition of alumina and zirconia as binders to the Fe-BEA led to a different effect on NO conversion. The catalytic activity of the mixed samples was evaluated by the temperature programmed procedure in a flow-reactor system, and the mechanism was analyzed via SEM, BET, XRD and XPS. It was found that larger iron particles were formed by the migration of parent iron particles in the Fe-BEA catalyst with alumina. This led to the increase of Fe magnitude and iron cluster, enhancing the abilities of NO oxidation and storage. Accordingly, the SCR activity increased slightly in low temperature but decreased sharply in high temperature. For the Fe-BEA with zirconia sample, NO oxidation and storage abilities decreased due to the less iron clusters. The increase of Fe magnitude resulted in higher catalytic oxidation ability, which gave rise to little change in the SCR activity compared with the Fe-BEA.

关键词： NH₃-SCR NO Fe-BEA Binder Alumina Zirconia

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Depth of cut models for multipass abrasive waterjet cutting of alumina ceramics with nozzle oscillation

Jun WANG

《机械工程前沿（英文）》 2010年第5卷第1期页码 19-32 doi: 10.1007/s11465-009-0082-1

摘要： An experimental study of the depth of cut in multipass abrasive waterjet (AWJ) cutting of alumina ceramics with controlled nozzle oscillation is presented. It is found that this cutting technique can significantly increase the depth of cut by an average of 50.8% as compared to single pass cutting without nozzle oscillation under the corresponding cutting conditions and within the same cutting time. Predictive models for the depth of cut are then developed. The modelling process starts with single pass cutting using a dimensional analysis technique and the particle erosion theories applied to alumina ceramics, before progressing to the development of the models for multipass cutting. The models are finally assessed both qualitatively and quantitatively with experimental data. It is shown that the model predictions are in good agreement with the experimental data with the average deviations of about 1%.

关键词： abrasive waterjet engineering ceramics depth of cut cutting performance nozzle oscillation machining

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Preparation and characterization of alumina hollow fiber membranes

Tao WANG, Yuzhong ZHANG, Guangfen LI, Hong LI

《化学科学与工程前沿（英文）》 2009年第3卷第3期页码 265-271 doi: 10.1007/s11705-009-0010-2

摘要： With the rapid development of membrane technology in water treatment, there is a growing demand for membrane products with high performance. The inorganic hollow fiber membranes are of great interest due to their high resistance to abrasion, chemical/thermal degradation, and higher surface area/volume ratio therefore they can be utilized in the fields of water treatment. In this study, the alumina (Al O ) hollow fiber membranes were prepared by a combined phase-inversion and sintering method. The organic binder solution (dope) containing suspended Al O powders was spun to a hollow fiber precursor, which was then sintered at elevated temperatures in order to obtain the Al O hollow fiber membrane. The dope solution consisted of polyethersulfone (PES), N-methyl-2-pyrrolidone (NMP) and polyvinylpyrrolidone (PVP), which were used as polymer binder, solvent and additive, respectively. The prepared Al O hollow fiber membranes were characterized by a scanning electron microscope (SEM) and thermal gravimetric analysis (TG). The effects of the sintering temperature and Al O /PES ratios on the morphological structure, pure water flux, pore size and porosity of the membranes were also investigated extensively. The results showed that the pure water flux, maximum pore size and porosity of the prepared membranes decreased with the increase in Al O /PES ratios and sintering temperature. When the Al O /PES ratio reached 9, the pure water flux and maximum pore size were at 2547 L/m ·h and 1.4 μm, respectively. Under 1600°C of sintering temperature, the pure water flux and maximum pore size reached 2398 L/(m ·h) and 2.3 μm, respectively. The results showed that the alumina hollow fiber membranes we prepared were suitable for the microfiltration process. The morphology investigation also revealed that the prepared Al O hollow fiber membrane retained its’asymmetric structure even after the sintering process.

关键词： Al₂O₃ ceramic membranes hollow fiber

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一水硬铝石氧化铝生产工艺创新

宋培凯

《中国工程科学》 2001年第3卷第8期页码 87-90

摘要：

论述了我国铝土矿的资源特点和氧化铝的生产现状，介绍了一水硬铝石管道化溶出新技术及实施效果，阐明了一水硬铝石溶出技术的发展方向和意义。

关键词：一水硬铝石氧化铝管道化溶出节能降耗磨损

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Selective catalytic reduction of NO

Pavlo I. Kyriienko

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 471-491 doi: 10.1007/s11705-019-1847-7

摘要： Research results regarding selective catalytic reduction (SCR) of NO with ethanol and other C oxygenates as reductants over silver-alumina catalysts are summarized. The aspects of the process mechanism, nature of active sites, role of alumina and silver (especially in the formation of bifunctional active sites), effects of reductants and reaction conditions are discussed. It has been determined that key stages of the process include formation of reactive enolic species, their interaction with NO and formation of nitroorganic compounds which transform to NCO species and further to N . The results obtained over various silver-alumina catalysts demonstrate the perspectives of their application for reducing the level of nitrogen oxides in engine emissions, including in the presence of water vapor and sulfur oxides. Ways to improve the catalysts for the SCR of NO with C oxygenates are outlined.

关键词： SCR nitrogen oxides silver-alumina catalyst silver species ethanol oxygenates

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Hydro-pyrolysis of lignocellulosic biomass over alumina supported Platinum, Mo

Songbo He, Jeffrey Boom, Rolf van der Gaast, K. Seshan

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 155-161 doi: 10.1007/s11705-017-1655-x

摘要： In-line hydro-treatment of bio-oil vapor from fast pyrolysis of lignocellulosic biomass (hydro-pyrolysis of biomass) is studied as a method of upgrading the liquefied bio-oil for a possible precursor to green fuels. The nobel metal (Pt) and non-noble metal catalysts (Mo C and WC) were compared at 500 °C and atmospheric pressure which are same as the reaction conditions for fast pyrolysis of biomass. Results indicated that under the pyrolysis conditions, the major components, such as acids and carbonyls, of the fast pyrolysis bio-oil can be completely and partially hydrogenated to form hydrocarbons, an ideal fossil fuel blend, in the hydro-treated bio-oil. The carbide catalysts perform equally well as the Pt catalyst regarding to the aliphatic and aromatic hydrocarbon formation (ca. 60%), showing the feasibility of using the cheap non-noble catalysts for hydro-pyrolysis of biomass.

关键词： bio-oil pyrolysis hydro-deoxygenation (HDO) non-noble metal catalysts hydro-treatment

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粉煤灰提取白炭黑和氧化铝的研究

荆富,伊茂森,张忠温,饶拴民

《中国工程科学》 2012年第14卷第2期页码 96-106

摘要：

粉煤灰是我国当前排量最大的工业废渣之一，年排渣量已达3亿t以上，大量堆积的粉煤灰会对自然生态环境造成严重的危害。综合利用粉煤灰，实现粉煤灰的资源化利用，对于治理粉煤灰的污染具有十分重要的意义。文章提出先采用碱液常压浸出粉煤灰，生产白炭黑，然后采用碱石灰烧结法生产氧化铝，可实现粉煤灰的经济综合利用。研究表明：用苛性碱液在常压（＜125 ℃）下浸取粉煤灰45 min，粉煤灰中硅的提取率达到72.5 %以上，而氧化铝的总溶出率＜1.2 %；碳分浸取得到的硅酸钠溶液，可以生产氧化硅含量＞99 %的优质白炭黑，溶液中氧化硅转化率＞98 %；浸取硅后的渣中氧化铝含量＞55 %，氧化硅含量＜20 %，铝硅比≥2.7，适宜采用碱石灰烧结法生产氧化铝。碱石灰烧结法适宜的配方为：碱比 0.95～1.0，钙比 1.8～2.0；烧结温度宜为1 200～1 250 ℃；熟料溶出温度75～85 ℃，时间10～20 min，氧化铝回收率＞86 %。综合利用粉煤灰生产白炭黑和氧化铝，经济效益和社会效益显著。

关键词：粉煤灰白炭黑氧化铝综合利用

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Tuning of the active phase structure and hydrofining performance of alumina-supported tri-metallic WMoNi

Shufeng Shan, Haiyan Liu, Gang Shi, Xiaojun Bao

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 59-69 doi: 10.1007/s11705-017-1686-3

摘要： The effects of phosphorus on the structure and hydrofining performance of tri-metallic WMoNi/Al O catalysts prepared with W/Mo-based hybrid precursor nanocrystals were investigated. The incorporation of phosphorus weakened the metal-support interactions (MSIs) and facilitated the formation of more synergetic NiWMoS phases with higher stacks. Catalytic tests using a fluid catalytic cracking diesel fuel showed that the changes in the MSIs and the morphology of the active phases had a more positive effect on the hydrodenitrogenation activity than on the hydrodesulfurization activity. In contrast, when phosphorus was incorporated into a tri-metallic WMoNiP/Al O catalyst prepared by a conventional incipient impregnation method, the MSIs decreased causing aggregation of the metal species which resulted in poorer hydrofining performance of the catalyst. These results show that incorporating phosphorus into a WMoNi/Al O catalyst can finely tune the structure of the active phase to enhance the hydrogenation and hydrodenitrogenation activity of the resulting tri-metallic catalyst.

关键词： fluid catalytic cracking diesel hydrofining performance WMoNiP/Al₂O₃ synergetic effect and structure of NiWMoS phases

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Enhanced methanation stability of nano-sized MoS

Zhenhua LI, Jia HE, Haiyang WANG, Baowei WANG, Xinbin MA

《化学科学与工程前沿（英文）》 2015年第9卷第1期页码 33-39 doi: 10.1007/s11705-014-1446-6

摘要： A series of unsupported MoS catalysts with or without Al O modification was prepared using a modified thermal decomposition approach. The catalysts were tested for the methanation of carbon monoxide and the optimum one has 25.6 wt-% Al O content. The catalysts were characterized by nitrogen adsorption measurement, X-ray diffraction and transmission electron microscopy. The results show that adding appropriate amount of Al O increases the dispersion of MoS , and the increased interaction force between MoS and Al O can inhibit the sintering of active MoS to some extent.

关键词： unsupported catalyst molybdenum sulfide stability alumina methanation